This seems serious, urgent and ugly at the same time. Documented at this thread:
In essence the Boolean tools won´t work when shapes are inside the bounding box of the largest object.
Unless I miss some hidden magic wand tool.
Cheers
Using the newest version as of today when I combine two shapes I don't get consistent results. See short movie.
Screen Recording 2019-07-02 at 10.38.38.mov